/* 2318 MOON_ARROW — 레이아웃·컴포넌트
 * 극단 미니멀 모노크롬. 순백 배경·잉크 화살표·1px 헤어라인 격자. 평면·여백 중심.
 * 성공(초록)/막힘(빨강) 플래시만 최소 기능색. Inter + JetBrains Mono.
 */
* { box-sizing: border-box; }
/* hidden 속성은 항상 우선 — .overlay/.board-cover/.side-panel/.start-screen 의 display 지정이 [hidden]을 덮지 않도록 */
[hidden] { display: none !important; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  color: var(--ink);
  background-color: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;   /* 보드가 아무리 커도 문서 가로 스크롤 금지(넘치면 .board-wrap 안에서만 스크롤) */
}
a { color: inherit; text-decoration: none; }
h1, h2, h3, h4 { font-weight: 700; line-height: 1.25; letter-spacing: -0.01em; }
.mono, .timer, .big-time, .dc-best, .dc-size, .progress { font-family: 'JetBrains Mono', ui-monospace, monospace; }

.wrap { width: 100%; max-width: 1040px; margin: 0 auto; padding: 0 18px; }
.sr-title, .sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

/* ---------- 헤더 ---------- */
.site-header { border-bottom: 1px solid var(--line); background: var(--surface); position: sticky; top: 0; z-index: 30; }
.header-in { display: flex; align-items: center; gap: 16px; height: 58px; }
.brand { display: flex; align-items: center; gap: 9px; font-weight: 800; font-size: 18px; letter-spacing: -0.02em; }
.brand .mark {
  display: inline-grid; place-items: center; width: 26px; height: 26px;
  border: 1px solid var(--line-strong); border-radius: 6px; color: var(--ink);
}
.brand .mark svg { width: 15px; height: 15px; }
.header-nav { display: flex; gap: 4px; margin-left: 10px; flex: 1; }
.header-nav a { padding: 7px 11px; font-size: 14px; color: var(--ink-2); border-radius: 6px; font-weight: 600; }
.header-nav a:hover { color: var(--ink); background: var(--surface-2); }
.header-tools { display: flex; align-items: center; gap: 8px; }
.icon-btn {
  display: inline-grid; place-items: center; width: 36px; height: 36px;
  border: 1px solid var(--line); background: var(--surface); color: var(--ink-2);
  border-radius: 7px; cursor: pointer; font-size: 15px;
}
.icon-btn:hover { color: var(--ink); border-color: var(--line-strong); }
.lang-select {
  height: 36px; border: 1px solid var(--line); background: var(--surface); color: var(--ink-2);
  border-radius: 7px; padding: 0 8px; font-size: 13px; font-family: inherit; cursor: pointer; max-width: 130px;
}

/* ---------- 게임 메인 ---------- */
.play-main { padding: 14px 0 30px; }
.play-area { max-width: 620px; margin: 0 auto; }
.play-top { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 10px; }
.hud { display: flex; align-items: center; gap: 10px; }
.hearts { display: inline-flex; gap: 3px; color: var(--ink); }
.hearts .heart { width: 20px; height: 20px; }
.hearts .heart.off { color: var(--line-strong); }
.hearts.hit { animation: heartHit .4s ease; }
@keyframes heartHit { 0%,100% { transform: translateX(0); } 25% { transform: translateX(-3px); color: var(--danger); } 75% { transform: translateX(3px); color: var(--danger); } }
.progress { font-size: 14px; color: var(--ink-2); font-variant-numeric: tabular-nums; }
.timer { font-size: 19px; font-weight: 600; color: var(--ink); min-width: 54px; text-align: center; font-variant-numeric: tabular-nums; }
.diff-label { font-size: 13px; color: var(--ink-2); font-weight: 600; padding: 3px 10px; border: 1px solid var(--line); border-radius: 999px; text-transform: capitalize; }

/* ---------- 보드 ---------- */
.board-wrap { position: relative; display: flex; justify-content: center; padding: 8px; margin: 0 auto; max-width: 100%; overflow-x: auto; }
#board {
  --cell: 56px;
  display: grid; gap: 1px;
  background: var(--line);
  border: 1px solid var(--line-strong);
  user-select: none; -webkit-user-select: none; touch-action: manipulation;
}
.cell {
  width: var(--cell); height: var(--cell);
  display: grid; place-items: center;
  background: var(--cell-bg); position: relative;
}
.cell.arrow { cursor: pointer; color: var(--fill); border: 0; padding: 0; }
.cell.arrow:hover { background: var(--surface-2); }
.cell .arw { width: 62%; height: 62%; transition: none; }
.cell.escaping { z-index: 6; transition: transform .2s ease-in, opacity .2s ease-in; transform: translate(var(--tx, 0), var(--ty, 0)); opacity: 0; }
.cell.shake { animation: shake .38s ease; }
@keyframes shake { 0%,100% { transform: translateX(0); } 20% { transform: translateX(-4px); } 40% { transform: translateX(4px); } 60% { transform: translateX(-3px); } 80% { transform: translateX(3px); } }
.cell.flash-ok { background: var(--ok-soft); }
.cell.flash-bad { background: var(--danger-soft); }
.cell.arrow.flash-bad { color: var(--danger); }
.cell.arrow.hintpulse { animation: hintpulse 1.2s ease; }
@keyframes hintpulse { 0%,100% { background: var(--cell-bg); } 30%,70% { background: var(--accent-soft); transform: scale(1.06); } }

.board-cover {
  position: absolute; inset: 8px; display: grid; place-items: center;
  background: var(--surface); color: var(--ink-2); font-weight: 600; font-size: 15px;
  border: 1px solid var(--line); cursor: pointer; z-index: 5;
}

/* ---------- 도구 ---------- */
.tools { display: flex; justify-content: center; flex-wrap: wrap; gap: 8px; margin: 18px auto 0; max-width: 460px; }
.tool-btn {
  display: inline-flex; align-items: center; justify-content: center;
  width: 52px; height: 52px; padding: 0; cursor: pointer;
  border: 1px solid var(--line); background: var(--surface); color: var(--ink-2); border-radius: 10px;
}
.tool-btn svg { width: 22px; height: 22px; }
.tool-btn:hover { color: var(--ink); border-color: var(--line-strong); }

/* ---------- 시작 화면 ---------- */
.start-screen { position: fixed; inset: 0; z-index: 55; background: var(--bg); overflow-y: auto; overflow-x: hidden; padding: 52px 20px 60px; display: flex; flex-direction: column; align-items: center; }
.start-head, .start-list, .daily-row, .start-links { width: 100%; max-width: min(460px, calc(100vw - 40px)); }
.start-head { margin: 0 auto 30px; text-align: center; }
.start-brand { display: inline-grid; place-items: center; width: 54px; height: 54px; margin: 0 auto 12px; border: 1.5px solid var(--ink); border-radius: 14px; color: var(--ink); }
.start-brand svg { width: 30px; height: 30px; }
.start-title { font-size: 27px; font-weight: 800; letter-spacing: -0.02em; margin: 0; }
.start-sub { margin-top: 6px; font-size: 14px; color: var(--ink-3); }
.start-list { width: 100%; max-width: 460px; margin: 0 auto; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.diff-card {
  display: flex; flex-direction: column; align-items: flex-start; gap: 4px;
  padding: 16px; border: 1px solid var(--line-strong); background: var(--surface);
  border-radius: 14px; cursor: pointer; text-align: left; font-family: inherit; color: var(--ink);
}
.diff-card:hover { border-color: var(--ink); }
.dc-fires { display: inline-flex; gap: 2px; color: var(--ink); height: 16px; }
.dc-fires svg { width: 15px; height: 15px; }
.dc-name { font-size: 17px; font-weight: 700; text-transform: capitalize; }
.dc-size { font-size: 12px; color: var(--ink-3); }
.dc-best { font-size: 12px; color: var(--ink-2); margin-top: 4px; }
.daily-row { max-width: 460px; margin: 12px auto 0; }
.daily-btn {
  width: 100%; display: flex; align-items: center; justify-content: space-between; gap: 10px;
  padding: 15px 18px; border: 1px solid var(--line-strong); background: var(--surface);
  border-radius: 14px; cursor: pointer; font-family: inherit; color: var(--ink); font-size: 15px; font-weight: 700;
}
.daily-btn:hover { border-color: var(--ink); }
.daily-btn.done { color: var(--ink-3); }
.daily-btn .ds { font-size: 13px; font-weight: 600; color: var(--ink-2); }
.start-links { max-width: 460px; margin: 24px auto 0; text-align: center; font-size: 13px; }
.start-links a { color: var(--ink-2); padding: 0 8px; }
.start-links a:hover { color: var(--ink); }

/* ---------- 광고 (애드핏 규정: 래퍼 border-radius/overflow 금지) ---------- */
.ad-wrap { margin: 26px auto 4px; display: flex; justify-content: center; }
.ad-grid { display: flex; flex-direction: column; align-items: center; gap: 14px; width: 100%; max-width: 672px; margin: 0 auto; }
.ad-grid[data-ad-layout="mixed"] { max-width: 760px; }
.ad-row { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; width: 100%; }
.ad-cell { min-height: 50px; }

/* ---------- FAB · 패널 ---------- */
.fab-stack { position: fixed; right: 18px; bottom: 18px; display: flex; flex-direction: column; gap: 10px; z-index: 40; }
.fab {
  display: inline-flex; align-items: center; gap: 8px; padding: 12px;
  border: 1px solid var(--line-strong); background: var(--surface); color: var(--ink);
  border-radius: 999px; cursor: pointer; font-family: inherit; font-size: 13px; font-weight: 600;
}
.fab svg { width: 18px; height: 18px; }
.fab:hover { border-color: var(--ink); }
.fab-txt { display: none; }

.side-panel {
  position: fixed; right: 18px; bottom: 84px; width: 300px; max-width: calc(100vw - 36px);
  background: var(--surface); border: 1px solid var(--line-strong); border-radius: 12px; z-index: 45; overflow: hidden;
}
.panel-head { display: flex; align-items: center; justify-content: space-between; padding: 13px 15px; border-bottom: 1px solid var(--line); }
.panel-head h3 { margin: 0; font-size: 15px; }
.panel-close { border: 0; background: none; color: var(--ink-3); font-size: 16px; cursor: pointer; }
.panel-body { padding: 15px; }
.row-btns { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; }
.ghost-btn { padding: 10px; border: 1px solid var(--line); background: var(--surface); color: var(--ink); border-radius: 8px; cursor: pointer; font-family: inherit; font-size: 13px; font-weight: 600; }
.ghost-btn:hover { border-color: var(--line-strong); }
.panel-backdrop { position: fixed; inset: 0; background: rgba(0,0,0,0.28); z-index: 42; }

/* ---------- 완료/실패 오버레이 ---------- */
.overlay { position: fixed; inset: 0; display: grid; place-items: center; background: rgba(0,0,0,0.42); z-index: 60; padding: 20px; }
.overlay-card { background: var(--surface); border: 1px solid var(--line-strong); border-radius: 16px; padding: 26px; width: 340px; max-width: 100%; text-align: center; }
.badge { display: inline-grid; place-items: center; width: 46px; height: 46px; margin: 0 auto 12px; border-radius: 50%; background: var(--accent-soft); color: var(--ink); }
.badge svg { width: 26px; height: 26px; }
.overlay-card.lose .badge { color: var(--danger); background: var(--danger-soft); }
.overlay-card h2 { margin: 0 0 4px; font-size: 21px; }
.big-time { font-size: 34px; font-weight: 700; color: var(--ink); margin: 6px 0; }
.ov-meta { color: var(--ink-2); font-size: 13px; margin-bottom: 16px; }
.btn-primary { display: inline-block; padding: 12px 20px; border: 0; border-radius: 10px; background: var(--ink); color: var(--bg); font-family: inherit; font-size: 15px; font-weight: 700; cursor: pointer; }
.ov-actions { display: flex; gap: 10px; justify-content: center; margin-top: 2px; }
.ov-actions .ghost-btn, .ov-actions .btn-primary { flex: 1; }

/* ---------- 문서 페이지 (about·기법·가이드·난이도) ---------- */
main { padding: 26px 0 40px; }
.doc { max-width: 760px; margin: 0 auto; }
.doc h1 { font-size: 30px; margin: 4px 0 10px; }
.doc h2 { font-size: 20px; margin: 30px 0 12px; padding-top: 8px; border-top: 1px solid var(--line); }
.doc p { margin: 0 0 14px; color: var(--ink); }
.doc ul, .doc ol { margin: 0 0 16px; padding-left: 20px; }
.doc li { margin: 6px 0; }
.lead { font-size: 17px; color: var(--ink-2); }
.muted { color: var(--ink-3); font-size: 13px; }
.breadcrumb { font-size: 13px; color: var(--ink-3); margin-bottom: 10px; }
.breadcrumb a { color: var(--ink-2); }
.breadcrumb a:hover { color: var(--ink); }
.card-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 12px; margin: 6px 0 18px; }
.card { display: block; padding: 15px; border: 1px solid var(--line); border-radius: 11px; background: var(--surface); }
.card:hover { border-color: var(--line-strong); }
.card .tag { display: inline-block; font-size: 11px; font-weight: 700; color: var(--ink-2); text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 6px; }
.card h3 { margin: 0 0 5px; font-size: 16px; }
.card p { margin: 0; font-size: 13px; color: var(--ink-2); }
.faq details { border: 1px solid var(--line); border-radius: 10px; padding: 4px 14px; margin-bottom: 8px; background: var(--surface); }
.faq summary { padding: 11px 0; font-weight: 600; cursor: pointer; }
.faq .a { padding: 0 0 12px; color: var(--ink-2); }
.pager { display: flex; justify-content: space-between; gap: 12px; margin: 22px 0; font-size: 14px; }
.pager a { color: var(--ink); font-weight: 600; }
.start-link { display: inline-block; margin-top: 6px; padding: 10px 18px; border-radius: 9px; background: var(--ink); color: var(--bg); font-weight: 700; }

/* ---------- 푸터 ---------- */
.site-footer { border-top: 1px solid var(--line); background: var(--surface); margin-top: 20px; }
.site-footer.mini { position: static; }
.footer-in { padding: 26px 0 20px; }
.footer-cols { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; max-width: 620px; }
.footer-cols h4 { margin: 0 0 8px; font-size: 12px; text-transform: uppercase; letter-spacing: 0.05em; color: var(--ink-3); }
.footer-cols a { display: block; padding: 3px 0; font-size: 14px; color: var(--ink-2); }
.footer-cols a:hover { color: var(--ink); }
.copyright { margin-top: 18px; padding: 14px 0 0; font-size: 12px; color: var(--ink-3); }
.site-footer.mini .copyright { margin: 0; padding: 14px 0; text-align: center; }

/* ---------- 반응형 ---------- */
@media (max-width: 720px) {
  .header-nav { display: none; }
  .footer-cols { grid-template-columns: 1fr 1fr; }
  .side-panel { right: 12px; left: 12px; width: auto; bottom: 78px; }
  .doc h1 { font-size: 25px; }
}
@media (max-width: 420px) {
  .footer-cols { grid-template-columns: 1fr; }
  .start-list { gap: 10px; }
}